BF-30972 exposes a race between node shutdown and ongoing transaction leading to a null WT_SESSION access: https://github.com/mongodb/mongo/blob/v7.0/src/mongo/db/storage/wiredtiger/wiredtiger_recovery_unit.cpp#L345.

There are other places WT_SESSION is accessed in this function. Need to find and fix all such places where a null WT_SESSION is accessed after WT is closed. 

This exists on v7.0.